ASSESSMENT OF GROUNDWATER QUALITY AND CONTAMINATION SOURCES IN TALUKA MIRWAH, DISTRICT KHAIRPUR, SINDH

Abstract

This study was conducted to assess the physico-chemical and trace metal quality of groundwater from seven villages of Taluka Thari Mirwah, District Khairpur, by analyzing 47 sampling locations. The objective was to evaluate the suitability of groundwater for drinking and domestic purposes in accordance with WHO and EPA Pakistan guidelines. Standard analytical methods were employed to measure pH, total hardness (TH), electrical conductivity (EC), total dissolved solids (TDS), chlorides (Cl⁻), sulfates (SO₄²⁻), nitrates (NO₃–N), alkalinity, sodium (Na), calcium (Ca), and trace metals including manganese (Mn), nickel (Ni), zinc (Zn), copper (Cu), cobalt (Co), chromium (Cr), iron (Fe), and cadmium (Cd). Results indicated that pH values were within the permissible limits, while elevated levels of TDS (1440.5 mg/L), chloride (788.76 mg/L), sulfate (296.63 mg/L), TH (1168 mg/L), and alkalinity (733.33 mg/L) exceeded the WHO/EPA guidelines in several locations. Additionally, sodium and calcium reached 504 mg/L and 462 mg/L, respectively, surpassing recommended limits. Trace metal concentrations varied, with the highest levels detected as Mn (0.421 mg/L), Ni (0.105 mg/L), Zn (0.593 mg/L), Cu (0.49 mg/L), Co (0.023 mg/L), Cr (0.033 mg/L), Fe (0.808 mg/L), and Cd (0.01 mg/L). These elevated values, particularly from areas surrounding Taluka Thari Mirwah, suggest potential health risks and indicate groundwater contamination. In conclusion, while the pH values confirm neutral conditions, the high concentrations of salts and heavy metals raise serious concerns regarding the potability and safety of groundwater in the studied villages, necessitating mitigation measures and regular monitoring.